Analysis of the Protogea of Leibnitz. 61 
where been formed by the force of rushing waters or other violence, 
as is proved by the correspondence of the strata on their opposite 
sides. 
9. For ascertaining the methods pursued by nature in the forma- 
tion of mineral substances, it would be of advantage to compare them 
with the results obtained in the laboratory. “‘Meque enim aliud est 
natura quam ars quedam magna.” He will say nothing respecting 
the production de novo of the metals, or the possibility of the con- 
version of one metal into another; but places the stories of the re- 
generation of gold in sands that have been washed, and of the re- 
fuse matter of a mine acquiring new riches, on the same footing with 
those relating to subterranean pigmy miners and the discovery of 
treasures by means of the divining rod, by men who, if you blind- 
fold them, will not detect the largest and best known veins. Metal- 
lic matter is drawn from some old mines in the Hartz, but it is 4 sedi- 
‘ment brought in by water. 
10. Native and artificial cinnabar, native zinc from the East Indies 
and that collected from the furnaces of the Hartz, native calamine 
and that which, rising in smoke from certain ores,. incrusts the same 
furnaces, are cited as examples of an agreement between the pro- 
duets of nature and those of art. 
11. Artificial resemble natural crystals, but the latter, whether 
produced by the refrigeration of a melted mass, evaporation or sub- 
limation, being the result of a more intense heat than we are able to 
create, and of a process much longer than ours, are harder and more 
perfect. The forms of insects and grass, and the liquids sometimes 
seen in rock crystal, favor the idea that it has been formed from a 
solution. 
12—15. Short and unimportant. Sa] ammoniac is raised by nat- 
ural sublimation and collected near Naples. Native gold and silver 
have been fused and received a form from the matrix in which they 
ie. Some mineral substances owe their form to the motion of wa- 
ter alone, as the rounded pebbles found cemented into a rock in the 
ps themselves; some are the effect of the combined agency of fire 
and water. 
_ 16. Of tufa, stalactites, and the caverns, whether great or small, 
'n which they are formed—also of a cavern which emitted a vapor 
that took fire from a candle and burned some of the workman. Toads 
_ Sometimes found alive in the rocks. 
